Lori L. Pounds

Morphologic characteristics of varicose veins: possible role of metalloproteinases☆

BACKGROUNDnAlthough varicose veins are a common cause of morbidity, etiologic factors predisposing to dilatation, elongation, and tortuosity of the saphenous vein and its tributaries are poorly understood. We compared histologic features of normal and varicose saphenous veins and investigated the role of enzyme or inhibitor imbalance in development of varicosities.nnnMETHODSnEight normal and 10 varicose (C(2,3)E(P,S)A(S)P(R,O)) vein segments were used for this analysis. Matrix metalloproteinase (MMP) expression and activity were analyzed with Western blotting and zymography. Venous architecture and protein localization were determined with histology and immunohistochemistry.nnnRESULTSnWestern blot analysis demonstrated the presence of MMP- 1, MMP-2, MMP-9, and MMP-12, as well as small quantities of tissue inhibitor of metalloproteinases (TIMP)-1 and TIMP-2 in protein isolates from normal and varicose veins. Both vein types demonstrated MMP-2, MMP-9, and MMP-12 activity by gelatin zymography, although varicose vein expressed less MMP-9 activity than normal vein did. Compared with normal veins, changes in varicose veins were not uniformly distributed along the circumference; areas of intimal thickening were often interspersed with focal areas of dilatation. Fragmentation of elastic lamellae and loss of circular and longitudinal muscle fibers were evident in the varicosities. Focal aggregates of macrophages were detected within the media and adventitia of both normal and varicose veins. MMP-1 and MMP-9 were expressed in both types of vein segments; however, their immunohistochemical localization was distinctly different. In normal vein, endothelial cells, occasional smooth muscle cells (SMC), and adventitial microvessels expressed MMP-1, whereas its expression was localized to fibroblasts, SMC, and endothelial cells throughout involved portions of varicose veins. MMP-9 was localized to endothelial cells, medial SMC, and adventitial microvessels in both normal and varicose veins, although varicose veins demonstrated increased medial smooth muscle cell staining. MMP-12 was found in SMC and fibroblasts in both normal and varicose veins. Neither TIMP-1 nor TIMP-2 were detected with immunohistochemistry in any specimens examined.nnnCONCLUSIONSnThere are distinct differences in the structural architecture and localization of MMP expression in normal and varicose veins. Although the changes observed are not sufficiently definitive to enable a causal relationship, they do suggest a possible mechanism for the alterations in matrix composition observed between normal and varicose veins.

A changing pattern of infection after major vascular reconstructions.

Wound and graft infection can occur in more than 40% of patients undergoing vascular reconstructions for peripheral arterial disease (PAD). A recent increase in the frequency and severity of infections, as well as a change in the microorganisms recovered, led us to undertake a retrospective case-controlled study of wound/graft infections at this institution. The medical records of all patients undergoing vascular reconstruction for PAD during the previous 36 months were reviewed. Patient demographics, graft location and conduit, infection location, causative microorganisms, and factors potentially associated with development of infection were recorded. Infections were classified according to a modification of the CDC criteria into superficial incisional, deep incisional, or involving the graft (body only, anastomosis without disruption, or anastomosis with disruption). Univariate and multivariate regression analyses were used to identify factors associated with the development of infection. Four hundred ten (84 aortic, 41 extraanatomic, and 285 infrainguinal) revascularization procedures were performed in 217 men and 193 women with a mean age of 62 years (range 43–88). The infection rate for the entire group was 11.0% (45/410). Eighty percent (36/45) occurred after infrainguinal reconstructions and 64% (29/45) of the infections involved the groin incision. Direct involvement of the graft occurred in 67% (30/45), and 27% (12/45) presented with anastomotic disruption. Of the infrainguinal infections, in situ and prosthetic reconstructions were associated with a significantly higher rate of infection than reversed vein grafts tunneled anatomically (p <0.001, chi-square analysis). Patients with nonautogenous grafts (24 expanded polytetrafluoroethylene and 2 bovine) presented with more advanced infections involving the graft (20/26 procedures) and were more likely to present with anastomotic disruption (11/26). Staphylococcus aureus was isolated in the majority of infections (64%) and in all cases involving graft disruption. Multivariate regression analysis identified the following factors associated with development of infection: previous hospitalization (p = 0.03), a younger age (p = 0.047), and the presence of a groin incision (p = 0.04). Twenty-five percent of graft infections resulted in major amputation, and 11% of patients with graft infection died as a result. The incidence, morbidity, and mortality of infections in vascular reconstructions for PAD are increasing dramatically, particularly in infrainguinal reconstructions involving groin incisions. Perioperative antibiotic selection should be modified to include coverage for all Staphylococcal subspecies and hospitalization before surgical procedures should be avoided.

Rupture of a Nonaneurysmal Aorta Secondary to Staphylococcus Aortitis A Case Report and Review of the Literature

Infectious aortitis has become increasingly uncommon and, when diagnosed, typically occurs in an immunocompromised elderly male with a history of Staphylococcus or Salmonella infection and underlying atheromatous cardiovascular disease. The authors report a case of a 74-year-old man with aortitis complicated by rupture secondary to Staphylococcus aureus infection. The patient presented with worsening abdominal pain and fever after being discharged from the emergency room 2 weeks before with back pain and leukocytosis diagnosed as urinary tract infection and bronchitis. Computed tomography (CT) imaging of the retroperitoneum on the first visit appeared normal. Repeat CT scan on the subsequent visit revealed a contained rupture of a nonaneurysmal aorta at the level of the diaphragm. The patient was taken to the operating room emergently for repair. An infected periaortic hematoma and a 1 cm perforation in the posterior aorta were found. The aorta was excised and the area debrided. Revascularization was performed using a 22 mm extruded polytetrafluoroethylene (ePTFE) interposition graft placed in situ. This case demonstrates that a high index of suspicion is required in diagnosing infectious aortitis and that the diagnosis may be delayed in many cases. Additionally, it may not be uncommon for the infected aorta to rupture without prior aneurysm formation.

Chronic kidney disease and dialysis access in women

Chronic kidney disease currently affects one in nine Americans and over 500,000 have progressed to failure requiring kidney replacement therapy, with nearly 45% being women. Clinical Practice Guidelines have been developed in an effort to synthesize the latest literature, particularly randomized controlled trials, to assist clinical decision making. Women have different levels of kidney function than men at the same level of serum creatinine and may also lose kidney function over time more slowly than men. Although the arteriovenous fistulae have long been recognized as the preferred access for hemodialysis, women are less likely to initiate dialysis with an arteriovenous fistula in place. In addition, the female sex is regarded as a risk factor for access failure as well for complications such as steal. This article reviews treatment of women with chronic kidney disease, focusing on the difficulties they are perceived to have with dialysis access.

Outcomes of Isolated Tibial Endovascular Intervention for Rest Pain in Patients on Dialysis

BACKGROUNDnTibial interventions for critical limb ischemia are frequent in patients with end-stage renal disease (ESRD) presenting with critical ischemia. The aim of this study was to examine impact of ESRD on the patient-centered outcomes following tibial endovascular Intervention for rest pain.nnnMETHODSnA database of patients undergoing lower extremity endovascular interventions between 2006 and 2016 was retrospectively queried. Patients with rest pain (Rutherford 4) were identified. Patients with claudication (Rutherford 1 to 3) and tissue loss (Rutherford 5 and 6) were excluded. Patients were categorized by the presence or absence of ESRD. Patient-orientated outcomes of clinical efficacy (CE; absence of recurrent symptoms, maintenance of ambulation, and absence of major amputation), amputation-free survival (AFS; survival without major amputation), and freedom from major adverse limb events (MALEs; above ankle amputation of the index limb or major reintervention new bypass graft, jump/interposition graft revision) were evaluated.nnnRESULTSnA total of 829 patients (56% male, average age 59xa0years; 658 nonhemodialysis [non-HD] and 171 HD) underwent isolated tibial intervention in one leg for rest pain. Technical success was 99% with a median of 2 vessels treated per patient. There was no difference in the distribution of Trans-Atlantic Inter-Society Consensus I lesions, but both the modified Society for Vascular Surgery (SVS) runoff score and the pedal runoff score were worse in the HD group. The 30-day major adverse cardiac events and 30-day MALEs were equivalent in both groups. CE was 38xa0±xa09% and 19xa0±xa08% at 5xa0years for the non-HD and HD groups, respectively (Pxa0<xa00.01). Overall, AFS was 45xa0±xa08% and 18xa0±xa09% at 5xa0years for the non-HD and HD groups, respectively (Pxa0<xa00.01). Freedom from MALE was 41xa0±xa09% and 21xa0±xa08% at 5xa0years for the non-HD and HD groups, respectively (Pxa0<xa00.01).nnnCONCLUSIONSnPatients with ESRD who present with rest pain have equivalent short-term outcomes to those not on dialysis but do not achieve long-term satisfactory CE and AFS after isolated tibial intervention for rest pain.

An evaluation of the availability, accessibility, and quality of online content of vascular surgery training program websites for residency and fellowship applicants

Background: Vascular surgery residency and fellowship applicants commonly seek information about programs from the Internet. Lack of an effective web presence curtails the ability of programs to attract applicants, and in turn applicants may be unable to ascertain which programs are the best fit for their career aspirations. This study was designed to evaluate the presence, accessibility, comprehensiveness, and quality of vascular surgery training websites (VSTW). Methods: A list of accredited vascular surgery training programs (integrated residencies and fellowships) was obtained from four databases for vascular surgery education: the Accreditation Council for Graduate Medical Education, Electronic Residency Application Service, Fellowship and Residency Electronic Interactive Database, and Society for Vascular Surgery. Programs participating in the 2016 National Resident Matching Program were eligible for study inclusion. Accessibility of VSTW was determined by surveying the Accreditation Council for Graduate Medical Education, Electronic Residency Application Service, and Fellowship and Residency Electronic Interactive Database for the total number of programs listed and for the presence or absence of website links. VSTW were analyzed for the availability of recruitment and education content items. The quality of VSTW was determined as a composite of four dimensions: content, design, organization, and user friendliness. Percent agreements and kappa statistics were calculated for inter‐rater reliability. Results: Eighty‐nine of the 94 fellowship (95%) and 45 of the 48 integrated residencies (94%) programs participating in the 2016 Match had a VSTW. For program recruitment, evaluators found an average of 12 of 32 content items (35.0%) for fellowship programs and an average of 12 of 32 (37%) for integrated residencies. Only 47.1% of fellowship programs (53% integrated residencies) specified the number of positions available for the 2016 Match, 20% (13% integrated residencies) indicated alumni career placement, 34% (38% integrated residencies) supplied interview dates, and merely 17% (18% integrated residencies) detailed the selection process. For program education, fellowship websites provided an average of 5.1 of 15 content items (34.0%), and integrated residency websites provided 5 of 14 items (34%). Of the fellowship programs, 66% (84.4% integrated residencies) provided a rotation schedule, 65% (56% integrated residencies) detailed operative experiences, 38% (38% integrated residencies) posted conference schedules, and just 16% (28.9% integrated residencies) included simulation training. Conclusions: The web presence of vascular surgery training programs lacks sufficient accessibility, content, organization, design, and user friendliness to allow applicants to access information that informs them sufficiently. There are opportunities to more effectively use VSTW for the benefit of training programs and prospective applicants.

A comparison of preoperative and intraoperative vein mapping sizes for arteriovenous fistula creation

Background: Duplex ultrasound (DUS) mapping of the veins and arteries of the upper extremity is a well‐established practice in arteriovenous fistula creation for long‐term hemodialysis access. Previous publications have shown that vein diameters varying from 2 to 3 mm are predictive of success. Regional anesthesia is known to result in vasodilation and thus to increase the diameter of upper extremity veins. This study compares the sizes of veins measured by preoperative DUS mapping with those obtained after regional anesthesia to determine whether intraoperative DUS results in increased vein diameters and thus changes in the operative plan. A second goal was to determine whether such changes resulted in functional access. Methods: This was a prospective observational study conducted between July 2013 and December 2014. Consecutive patients were preoperatively mapped and then intraoperatively mapped after administration of a regional anesthetic. Comparison of vein mapping sizes and comparison of preoperative plan and operative procedure based on the preoperative and intraoperative DUS mapping, respectively, were analyzed with a repeated‐measures linear model. Significance testing was two sided, with a significance level of 5%. Results: Sixty‐five patients with end‐stage renal disease underwent placement of arteriovenous access with preoperative and intraoperative DUS mapping after regional anesthesia. Comorbidities were representative of the vascular population. After regional anesthesia, intraoperative mid forearm and distal forearm cephalic veins were significantly larger than their respective preoperative measurements. Average increase in diameter of the mid forearm cephalic vein and distal forearm was 0.96 mm (P < .001) and 0.50 mm (P = .04), respectively. There was a significant difference in the number and configuration of arteriovenous accesses (P < .0001). There was more than a twofold significant increase in radial artery‐based access procedures concomitant with a significant reduction of brachial‐based access procedures and a reduction in graft access procedures. Overall functional access rate was 63%, and patency rates were comparable to those reported in the literature. Conclusions: The routine use of intraoperative DUS mapping after regional anesthesia is recommended to determine the optimal access site for chronic hemodialysis access. Identifying additional access options not seen with physical examination and preoperative DUS mapping will provide end‐stage renal disease patients with more fistula options and hence a longer access life span for a lifelong disease.

Outcomes of Isolated Tibial Endovascular Interventions for Rest Pain in Patients on Dialysis

Study design: Single-center review between September 2013 and April 2015. Key findings: There were 30 patients who underwent preoperative computed tomograqphy angiography (CTA) and noncontrast enhanced magnetic resonance imaging (NC-MRI) at a maximum interval of 60 days prior to endovascular aneurysm repair (EVAR). Two expert readers (vascular radiologist and vascular surgeon) reviewed CTA images and chose the proper endograft for each patient. A vascular radiologist and a resident radiologist reviewed CTA and NCMRI examinations in a double-blind fashion. MRI sensitivity and specificity compared with CTA were 94% and 100%, respectively. CTA and NC-MRI angiographic measurements showed strong correlation, except for external iliac artery diameters. The choice of stent size was always the same between the two observers. Conclusion: Although CTA remains the gold standard, NC-MRI is a good alternative for EVAR planning such as for patients with renal impairment. Commentary: The paper suggests that NC-MRI is a suitable alternative for CTA when planning EVAR. This imaging alternative most readily applies to patients with chronic renal failure where contrast would be contraindicated. Although gadolinium-enhanced MRA has been (rarely) associated with nephrogenic systemic fibrosis in patients with renal failure, omission of contrast when performing MRI, as in this report, would avoid this complication. The biggest concern for the vascular surgeon who is not experienced interpreting MRIs is relying on a radiologist to provide accurate measurements for EVAR planning based on NC-MRI. Nonetheless, NC-MRI may prove to be a valuable alternative when planning EVAR in patients with renal impairment by avoiding the use of contrast with CTA. However, we have successfully used noncontrast-enhanced CT scans to plan EVAR in patients with renal insufficiency. My question is which study is more accurate and reliable in patients requiring complicated endovascular repairs who have underlying renal insufficiency: CT scan without contrast or MRI without contrast?

Outcomes of reintervention for recurrent symptomatic disease after tibial endovascular intervention

Objective Tibial interventions for critical limb ischemia are now commonplace. Restenosis and occlusion remain barriers to durability after intervention. The aim of this study was to examine the patient‐centered outcomes of open and endovascular reintervention for symptomatic recurrent disease after a primary isolated tibial endovascular intervention. Methods A database of patients undergoing isolated primary lower extremity tibial endovascular interventions between 2006 and 2016 was retrospectively queried. Patients with recurrent critical ischemia (Rutherford 4 and 5) were identified. Outcomes in this cohort were analyzed, and three groups were defined: endovascular reintervention (ie, a repeated tibial or pedal endovascular intervention), bypass (bypass to a tibial or pedal vessel), and primary amputation (ie, above‐ or below‐knee amputation) on the ipsilateral leg. Patient‐oriented outcomes of clinical efficacy (absence of recurrent signs or symptoms of critical ischemia, maintenance of ambulation, and absence of major amputation), amputation‐free survival (survival without major amputation), and freedom from major adverse limb events (above‐ankle amputation of the index limb or major reintervention, such as new bypass graft or jump or interposition graft revision) were evaluated after the reintervention. Results There were 1134 patients (56% male; average age, 59 years) who underwent primary tibial intervention for critical ischemia, and 54% presented with symptomatic restenosis and occlusion. Of the 513 patients with recurrent disease, 58% presented with rest pain and the remainder with ulceration. A repeated tibial endovascular intervention was performed in 64%, open bypass in 19%, and below‐knee amputation in 17%. Bypass was employed in patients with a good target vessel, venous conduit, and good pedal runoff. Patient‐centered outcomes were better in the bypass group compared with the reintervention group (amputation‐free survival, 45% ± 9% vs 27% ± 9% [P < .01]; major adverse limb events, 50% ± 9% vs 31% ± 9% [P < .05]; clinical efficacy, 60% ± 7% vs 30% ± 9% [P < .01], mean ± standard error of the mean at 5 years). Conclusions Tibial interventions for critical ischemia are associated with a high rate of reintervention. In patients with good target vessel, venous conduit, and good pedal runoff, bypass appears more durable than repeated tibial endovascular intervention.

Outcomes of upper extremity interventions for chronic critical ischemia

Background: Critical hand ischemia owing to below‐the‐elbow atherosclerotic occlusive disease is relatively uncommon. The aim of this study was to examine the outcomes in patients presenting with critical ischemia owing to below‐the‐elbow arterial atherosclerotic disease who underwent nonoperative and operative management. Methods: A database of patients undergoing operative and nonoperative management for symptomatic below‐the‐elbow atherosclerotic disease between 2006 and 2016 was retrospectively queried. Patients with critical ischemia (tissue loss and rest pain) were identified. Three management groups were identified: no revascularization (None), endovascular revascularization (Endo), and open revascularization by bypass (Bypass). Patients with acute embolism, active vasculitis, end‐stage renal disease, ipsilateral dialysis access complications of steal, and ipsilateral trauma were excluded. Results: One hundred eight patients (56% male; average age, 59 years) presented with symptomatic below‐the‐elbow disease: 93% presented with digital ulceration and the remainder with rest pain. Eighty‐one percent had diabetes and 41% had chronic renal insufficiency (not on dialysis). All underwent catheter‐based angiography. Fifty‐three patients (49%) had no intervention and subsequently were committed to wound care; 26 of these required no further intervention, 10 had an interval palmar sympathectomy, and 17 underwent either a phalanx or digital amputation. Thirty‐four patients (31%) underwent an endovascular intervention with a median of 1.5 vessels (ulnar, radial, or interosseous arteries) intervened on. Technical success was achieved in 29 patients (85%). Of the five technical failures, two went on to bypass, one had a focal endarterectomy and patch angioplasty, and one was treated conservatively. Ten patients in the Endo group required either a phalanx or digital amputation. Twenty‐one patients (19%) underwent a saphenous vein bypass (reversed or nonreserved) to the radial in 12 and the ulnar in 11 limbs. In follow‐up, 11 patients underwent open or endovascular intervention to maintain patency of the bypass. There were nine phalanx or digital amputations in the Bypass group. No below‐the‐elbow or above‐the‐elbow amputations were performed within 30 days. The wound healing rate without amputation was 78% (85 of 108). The predictors of wound healing were technical success of the revascularization, intact palmar arch and presence of digital run‐off. The presence of an incomplete arch and poor digital run‐off were associated with a phalanx or digital amputation. Conclusions: Upper extremity interventions for critical ischemia are associated with a high rate of success. Major amputations are rare and the many can be treated nonoperatively. In appropriately selected patients, both endovascular and open interventions have a high rate of success.